JP3725510B2 - Rotor of abduction type permanent magnet motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotor of an outer rotation type permanent magnet motor having a plurality of magnetic poles arranged in an annular shape located on the outer periphery of a stator.
[0002]
[Prior art]
Conventionally, the rotor shown in FIGS. 10 and 11 is provided as the rotor of the outer rotation type permanent magnet motor. This has a permanent magnet 2 on the inner peripheral part (inside the peripheral side wall 1b) of a frame 1 in which a circular main plate part 1a and an annular peripheral side wall 1b positioned around the main part are formed of a magnetic material such as an iron plate. A plurality of magnetic poles 3 are arranged in a ring shape by arranging the number of magnetic poles as many as the number of magnetic poles. On the other hand, a ring member 4 also formed of a magnetic material is arranged on the outer peripheral portion of the frame 1 (outside the peripheral side wall 1b) The permanent magnets 2 (magnetic poles 3) are positioned around the outer periphery of a stator (not shown) and rotate (for example, for example). Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent No. 3017953 (page 3, FIGS. 1 to 3)
[0004]
[Problems to be solved by the invention]
In the case of the above conventional one, the method shown in FIG. That is, in the configuration in which the molding die 6 is composed of the lower die 6a and the upper die 6b covering the lower die 6a, the permanent magnet 2 is provided in each of the recesses 7 formed in the lower die 6a in accordance with the shape and the number of the permanent magnets 2. It is inserted and arranged in an annular shape, and the frame 1 is covered from above, and a ring member 4 is placed on the outer periphery thereof. Then, the upper mold 6b is put on the mold, and the mold is clamped. Thereafter, the cavity 8 between the upper mold 6b and the lower mold 6a is filled with the synthetic resin 5 in a molten state. And when the synthetic resin 5 hardens | cures, the upper mold | type 6b is removed and the whole rotor is picked up from the lower mold | type 6a.
[0005]
For this reason, it is necessary to form a plurality of recesses 7 corresponding to the shape and the number of the permanent magnets 2 for arranging the permanent magnets 2 corresponding to the number of the magnetic poles 3 in the lower die 6a. However, the problem is that the product price becomes high.
[0006]
The present invention has been made in view of the above-described circumstances, and therefore the object thereof is mainly to provide a rotor of an outer rotation type permanent magnet motor that can simplify a mold and reduce the product price. In offer.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a rotor of an outer rotation type permanent magnet motor of the present invention is provided with a frame, an iron core provided around the frame, each having a hole in a portion forming a magnetic pole, A plurality of permanent magnets inserted into the holes, and the inner peripheral portion of the portion forming the magnetic pole of the iron core has a shape in which the air gap between the stator and the stator is uneven in the circumferential direction And a trough portion having a depth reaching the outer peripheral side from the center of the maximum radial direction width of the core between the portions forming the magnetic poles of the core, and the outer peripheral side from the center of the maximum radial direction width of the core And a passage filled with a synthetic resin that integrally couples the frame, the iron core, and the permanent magnet, and the synthetic resin is molded between the portions forming the magnetic poles of the iron core. characterized in that the (first aspect of the present invention).
According to this, the permanent magnet may be inserted into the hole formed in the iron core, and it is not necessary to form a concave portion for positioning the permanent magnet by inserting the permanent magnet into the molding die. Product price can be reduced.
In addition, the distribution of magnetic flux density in the air gap between the rotor and the stator can be reduced in torque ripple, and the magnetic flux between adjacent permanent magnets is prevented from being short-circuited by the valleys. The flow of the magnetic flux can be improved, and the passage of the synthetic resin that integrally couples the frame, the iron core, and the permanent magnet is provided to the magnetic flux on the inner peripheral side (stator side) between the adjacent permanent magnets. The flow can be prevented from being hindered, and the magnetic force can be exerted on the stator in a good manner, and the frame, the iron core, and the permanent magnet can be more firmly coupled by the synthetic resin.
[0012]
Hole of the core may laterally of the permanent magnet inserted into it, and the frame, core, and to have a stepped exhaustive space to be filled through the synthetic resin to bind together the permanent magnets. (Invention of Claim 2 ).
In this case, the permanent magnet can be firmly fixed in the hole of the iron core while sufficiently securing the passage of the synthetic resin.
[0013]
Further, the iron core may have a recessed portion filled with a synthetic resin that integrally couples the frame, the iron core, and the permanent magnet in communication with the outer peripheral side of the hole (invention of claim 3 ). .
In this case, the permanent magnet can be securely fixed in the hole of the iron core by moving the permanent magnet toward the inner peripheral side of the hole by the synthetic resin filled in the recessed portion on the outer peripheral side of the hole.
In addition, the dimension of the iron core from the hole to the outer peripheral side may be made larger than the dimension from the hole to the inner peripheral side (invention of claim 4 ).
This can improve the flow of magnetic flux on the outer peripheral side from the hole in the iron core.
[0014]
Further, the iron core may be configured by combining unit iron cores formed by being divided into a plurality of parts (invention of claim 5 ).
In this case, the magnetic resistance is increased at the joint of the unit cores, so that the magnetic force is smaller in the part than in the other part, and the rotation of the rotor is slowed down in that part. Based on this, in a motor that performs feedback control, the current and voltage values increase in order to speed up the rotation. By measuring the increased current and voltage values, detection of the rotational position of the rotor, and consequently the rotation load The rotational position can be detected.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of the present invention will be described below with reference to FIGS.
First, FIG. 4 shows a stator 11 of an outer rotation type permanent magnet motor, which mainly comprises an iron core 12 and a coil 13.
[0016]
Among them, the iron core 12 is constituted by laminating a large number of silicon steel plates, which are magnetic bodies punched into a predetermined shape, for example, and an annular yoke portion 12a and a large number of teeth projecting radially from the outer peripheral portion thereof. And a covering member 14 made of a synthetic resin, which is an electrical insulating material, is provided on the outer surface of the entire portion. The covering member 14 is formed with a plurality of attachment portions 15 on the inner peripheral portion thereof, whereby the stator 11 is attached to a motor attachment portion of necessary equipment such as a washing machine. And each teeth part 12b winds the coil 13 around each outer periphery of the coating | coated member 14, and the stator 11 is comprised by the above.
[0017]
On the other hand, FIGS. 6 and 7 and FIGS. 1 to 3 show the rotor 16 of the abduction-type permanent magnet motor, which mainly includes the frame 17, the iron core 18, and the permanent magnet 19. It is made up. Of these, the frame 17 is formed by pressing, for example, an iron plate, which is a magnetic material. As shown in FIG. 5, a circular main plate portion 17a having a shaft support forming hole 20 in the center, and this main plate. It has a flat covered cylindrical shape having an annular peripheral side wall 17b depending from the outer peripheral portion of the portion 17a.
[0018]
A stepped portion 21 is also formed on the outer peripheral portion of the main plate portion 17a over the entire periphery, and the iron core 18 is provided in the peripheral portion of the frame 17 as shown in FIG. As shown in FIG. 2, it is arranged in a space surrounded by the step portion 21 and the peripheral side wall 17b so that the inner peripheral edge of the step portion 21 and the inner peripheral surface of the iron core 18 are substantially flush with each other. Yes. A plurality of holes 22 shown in FIG. 3 are formed in the stepped portion 21 over the entire circumference. Further, a portion of the main plate portion 17a between the stepped portion 21 and the shaft support forming hole 20 is shown in FIG. As shown in FIG. 5 and FIG. 6, a plurality of ventilation holes 23 are formed in an annular arrangement.
[0019]
In this case, the iron core 18 is configured by laminating, for example, a large number of iron plates, which are magnetic bodies punched in a generally annular shape, and the portion of the iron core 18 where the plurality of magnetic poles 24 are formed Each hole 25 is formed. As shown in FIG. 2, the hole 25 has a depth reaching from the lower end surface of the iron core 18 to the vicinity of the upper end surface. As shown in FIG. 1, the hole 25 has a rectangular narrow portion 25 a long in the tangential direction of the iron core 18. It has a so-called two-stage shape having a wide portion 25b on the outer peripheral side, which is the same rectangular shape and wider than that, and the step 26 is between both side portions of the narrow portion 25a and the wide portion 25b. Exists.
[0020]
Further, on the outer peripheral side of the hole 25 (the outer peripheral side of the wide portion 25b), a semi-cylindrical recess 27 that communicates with the hole 25 is formed at the center. Further, a through hole 28 that penetrates the iron core 18 in the axial direction is formed between the portions of the iron core 18 where the magnetic poles 24 are formed so as to be positioned on the outer peripheral side from the center O of the radial width W of the iron core 18. At the same time, the trough 29 is formed from the inner peripheral side of the iron core 18 to a depth reaching the outer peripheral side from the center O of the radial maximum width W of the iron core 18 as shown in FIG.
[0021]
In addition, the inner peripheral portion 30 of the portion of the iron core 18 that forms the magnetic pole 24 has a shape in which the air gap between the stator 11 and the stator 11 facing it is non-uniform in the circumferential direction. Further, a dimension B from the hole 25 to the outer peripheral side is made larger than the dimension A from the hole 25 to the inner peripheral side of the iron core 18.
[0022]
On the other hand, the permanent magnet 19 has a rectangular flat plate shape, and is inserted into the hole 25 of the iron core 18, particularly the narrow portion 25a. As a result, in the hole 25, the entire narrow portion 25a is filled with the permanent magnet 19, and the permanent magnet 19 is also located in a part of the wide portion 25b. Due to the above-described step 26, spaces 31 are left on both sides of the wide portion 25b (on both sides of the inserted permanent magnet 19). In addition, the permanent magnet 19 is magnetized in the thickness direction, and its magnetic force has a high energy product of about 2370 [MA / m] (reference value: 30 [MOe]) or more.
[0023]
FIG. 8 shows a molding die 32 used for manufacturing the rotor 16, and the molding die 32 includes a lower die 32a and an upper die 32b covering the lower die 32a. The iron core 18 in which the permanent magnet 19 is inserted into the hole 25 is placed on the outer periphery of the convex portion 33 of the lower mold 32a, covered with the frame 17, and further covered with the upper mold 32b and clamped. Thereafter, the synthetic resin 35 is filled in the molten state into the cavity 34 between the upper mold 32b and the lower mold 32a.
[0024]
Then, as shown in FIG. 3, the synthetic resin 35 is filled through the through hole 28 of the iron core 18, and is filled between the iron core 18 and the step portion 21 of the frame 17 and passes through the hole 22. Molded to be located outside. Accordingly, the through hole 28 of the iron core 18 functions as a passage through which the synthetic resin 35 is filled.
[0025]
At this time, as shown in FIG. 1, the synthetic resin 35 is injected and filled in the hole 25 of the iron core 18 into which the permanent magnet 19 is inserted, particularly in the wide portion 25b thereof. Spaces 31 on both sides of the portion 25b (on both sides of the permanent magnet 19) function as a passage filled with the synthetic resin 35.
[0026]
Further, at this time, the synthetic resin 35 is also injected into and filled in the recessed portion 27 of the iron core 18, whereby the iron core 18 is brought closer to the inner peripheral side of the hole 25 (the inner peripheral side of the narrow portion 25 a). . In addition, the synthetic resin 35 is filled in the troughs 29, so that as shown by the molding part 36 in FIGS. It is filled and molded between the surfaces (the side opposite to the bottom side of the valley portion 29). Further, as shown in FIG. 6, the synthetic resin 35 reaches the shaft support body forming hole 20 portion of the frame 17 to form a shaft support body 37, and a plurality of ribs 38 extending radially around the shaft support body 37. Form. Thus, the frame 17, the iron core 18, and the permanent magnet 19 are integrally coupled by the synthetic resin 35, and the rotor 16 is manufactured.
[0027]
The molding die 32 removes the upper die 32b when the synthetic resin 35 is cured, and picks up the entire rotor 16 from the lower die 32a. The rotor 16 is then attached to a rotary shaft (not shown) on the shaft support 37, and this rotary shaft is rotatably supported by a bearing holder (also not shown) via a bearing (not shown). A plurality of magnetic poles 24 formed by inserting the permanent magnets 19 into the holes 25 of the iron core 18 are rotated around the outer periphery of the stator 11 in an annular arrangement.
[0028]
As described above, according to the rotor 16 of the outer rotation type permanent magnet motor of this configuration, the permanent magnet 19 may be inserted into the hole 25 formed in the iron core 18 at the time of manufacture, and the concave portion formed in the conventional mold 6. Therefore, it is not necessary to form the concave portion 7 or the like in the molding die 32, so that the molding die 32 can be simplified and the product price can be reduced.
[0029]
Further, in the case of this configuration, the inner peripheral portion 30 of the portion forming the magnetic pole 24 of the iron core 18 has a shape in which the air gap between the stator 11 and the stator 11 is not uniform in the circumferential direction. The magnetic resistance in the gap is also non-uniform in the circumferential direction, and the distribution of magnetic flux density in the air gap can be reduced in torque ripple. As one of them, in the case of the above configuration in which the inner peripheral portion 30 of the iron core 18 forming the magnetic pole 24 is formed in a medium-high arc surface shape, the magnetic resistance in the air gap is set at the central portion of the inner peripheral portion 30. As a result, the magnetic flux density in the air gap can be made close to a sine wave with a waveform, and there is less space harmonics, resulting in less torque ripple. Generation of vibration and noise can be reduced.
[0030]
Further, between the portions of the iron core 18 where the magnetic poles 24 are formed, there is a trough portion 29 having a depth reaching the outer peripheral side from the center O of the radial maximum width W of the iron core 18, thereby allowing the adjacent permanent portions. The short circuit of the magnetic flux between the magnets 19 can be prevented by the trough 29, and the flow of the magnetic flux can be improved (the magnetic flux can flow on the outer peripheral side between the adjacent permanent magnets 19).
[0031]
The frame 17, the iron core 18, and the permanent magnet 19 are integrally coupled with a synthetic resin 35, and the through hole 28 that is a passage filled with the synthetic resin 35 passes through the center O of the iron core 18 with the maximum radial width W. It is on the outer peripheral side. Thereby, the passage (through hole 28) of the synthetic resin 35 can be prevented from interfering with the flow of magnetic flux on the inner peripheral side (stator 11 side) between the adjacent permanent magnets 19, and the magnetic force is applied to the stator. It can be made well.
[0032]
In addition, the synthetic resin 35 is molded between the portions of the iron core 18 where the magnetic poles 24 are formed (molded portion 36). Thereby, the coupling | bonding of the flame | frame 17, the iron core 18, and the permanent magnet 19 by the synthetic resin 35 can be strengthened more.
Further, the hole 25 of the iron core 18 has a step 26 that leaves a space 31 filled with the synthetic resin 35 through the side of the permanent magnet 19 inserted therein. Thereby, the permanent magnet 19 can be firmly fixed in the hole 25 of the iron core 18 while sufficiently securing the passage of the synthetic resin 35.
[0033]
In addition, the iron core 18 has a recess 27 that is filled with a synthetic resin 35 on the outer peripheral side of the hole 25 in communication, so that the permanent magnet 19 can be fixed in the hole 25 of the iron core 18. The permanent magnet 19 can be brought close to the inner peripheral side of the hole 25 by the synthetic resin 35 filled in the notch 27 and can be surely obtained.
In addition, the dimension B from the hole 25 to the outer peripheral side of the iron core 18 is made larger than the dimension A from the hole 25 to the inner peripheral side. As a result, a wide magnetic flux path can be secured on the outer peripheral side from the hole 25 of the iron core 18, and the flow of magnetic flux can be improved.
[0034]
In contrast to this, FIG. 9 shows a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof will be omitted, and only different parts will be described.
In this structure, the iron core 18 is configured by combining unit iron cores 18 a formed by dividing into a plurality of pieces as indicated by a joint 41.
[0035]
In this case, the magnetic resistance increases at the joint 41 of the unit iron core 18a, and the magnetic force becomes smaller in the portion than in other portions. For this reason, the rotation of the rotor 11 is slowed at the portion where the magnetic force is reduced, and based on this, the current and voltage value are increased in order to speed up the rotation of the motor that performs feedback control. Therefore, by measuring the increased current and voltage values, it is possible to detect the rotational position of the rotor 16 and thus the rotational position of the rotational load.
[0036]
In addition, in this case, since the size of the unit iron core 18a is reduced, there is an effect that the material removal from the material of the iron core 18 can be improved.
In addition, this invention is not limited only to each Example mentioned above and shown in drawing, In the range which does not deviate from a summary, it can change suitably and can implement.
[0037]
【The invention's effect】
As described above, according to the rotor of the outer rotation type permanent magnet motor of the present invention, it is not necessary to form a concave portion or the like for positioning by inserting the permanent magnet into the molding die, so that the molding die can be simplified. Can be achieved, and the product price can be reduced. In addition, the magnetic flux density distribution in the air gap between the rotor and the stator can be reduced in torque ripple, and the magnetic flux between adjacent permanent magnets is prevented from being short-circuited by the valleys. The flow of the magnetic flux can be improved, and the passage of the synthetic resin that integrally couples the frame, the iron core, and the permanent magnet is provided to the magnetic flux on the inner peripheral side (stator side) between the adjacent permanent magnets. The flow can be prevented from being hindered, and the magnetic force can be exerted on the stator in a good manner, and the frame, the iron core, and the permanent magnet can be more firmly coupled by the synthetic resin.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part of a rotor showing a first embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of the main part taken along line XX of FIG. Fig. 4 is a perspective view of the entire stator. Fig. 5 is a perspective view of the frame of the rotor. Fig. 6 is a bottom view of the entire rotor. Fig. 7 is a partial perspective view of the rotor. FIG. 8 is a longitudinal side view showing a manufacturing process of a rotor using a mold. FIG. 9 is a view corresponding to FIG. 1 showing a second embodiment of the invention. FIG. 10 is a longitudinal sectional view of the whole rotor showing a conventional example. 11 is a diagram corresponding to FIG. 1. FIG. 12 is a diagram corresponding to FIG.
11 is a stator, 16 is a rotor, 17 is a frame, 18 is an iron core, 18a is a unit iron core, 19 is a permanent magnet, 24 is a magnetic pole, 25 is a hole, 26 is a step, 27 is a recess, and 28 is a through hole. (Passage), 29 is a trough, 30 is an inner peripheral portion of a portion forming a magnetic pole of an iron core, 31 is a space, 32 is a molding die, 35 is a synthetic resin, 36 is a molding portion, 41 is a joint of unit cores, A Is a dimension on the inner peripheral side from the hole in the core, B is a dimension on the outer peripheral side from the hole in the core, W is the maximum radial width of the core, and O is the center of the maximum radial width of the core.

Claims (5)

In what has a plurality of magnetic poles arranged in an annular shape located on the outer periphery of the stator,
Frame,
An iron core provided around the frame and having a hole in each of the portions forming the magnetic pole;
A plurality of permanent magnets inserted into the holes of the iron core;
Equipped with,
The inner peripheral part of the part forming the magnetic pole of the iron core is shaped so that the air gap between the stator and the stator is not uniform in the circumferential direction,
Between the portions forming the magnetic poles of the iron core, having a trough having a depth reaching the outer peripheral side from the center of the maximum radial width of the iron core,
And, on the outer peripheral side from the center of the maximum radial width of the iron core, the frame, the iron core, and a passage filled with a synthetic resin that integrally couples the permanent magnet are filled,
A rotor of an abduction type permanent magnet motor, characterized in that the synthetic resin is molded between portions forming magnetic poles of an iron core . 2. The hole of the iron core has a level difference on the side of the permanent magnet inserted therein, leaving a space filled with a synthetic resin for integrally bonding the frame, the iron core, and the permanent magnet. The rotor of the described outer rotation type permanent magnet motor. 2. The outer rotation according to claim 1 , wherein the iron core has a recessed portion filled with a synthetic resin that integrally couples the frame, the iron core, and the permanent magnet in communication with the outer peripheral side of the hole. Rotor of a permanent magnet motor. 2. The rotor of an outer rotation type permanent magnet motor according to claim 1 , wherein a dimension of the iron core from the hole to the outer peripheral side is larger than a dimension from the hole to the outer peripheral side . 2. The rotor of an abduction type permanent magnet motor according to claim 1, wherein the iron core is configured by combining unit iron cores formed by being divided into a plurality of parts .

Images